Derrick elevator



DERRICK ELEVATOR Filed April 5, 1940 2 5 INVENTOR.

BY CPA wro/eo l6. 5m; M46011 gum/1M5 ATT RNEY.

Patented Feb. 25, 1941 UNITED STATES PATENT OFFICE DERRICK ELEVATORCrawford K. Stillwagon, Houston, Tex.

Application April 5, 1940, Serial No. 327,970

2 Claims.

This invention relates to 'a derrickelevator.

An object of the invention to provide an elevator specially adapted foruse in connection with derricks such as are commonly used'in oil fields.

Another object of the invention is to provide a derrick elevator wherebythe derrick man may be safely elevated to his place of work in theelevator and may safely descend.

The elevator is so constructed that the derrick man, in case of fire,may be quickly, easily and safely lowered to the ground surface and beprotected from the fire while descending.

The invention further embodies a novel type 15 of brake mechanismnormally held inactive by the cable from which the elevator car -'issuspended but which will become active in case of breakage of the cableto prevent the elevator car from suddenly dropping to the ground sur- 20face and injuring the occupants of the car.

It is a further object of the invention to provide elevator equipmentfor a derrick which is of such construction that it may be readilydismantled when the derrick is to be moved and 2c readily reinstalled onthe derrick at a new location.

With the above and other objects in view the invention has particularrelation to certain novel features of construction, operation andarrange- 30 ment of parts, an example of which is given in thisspecification and illustrated in the accompany drawing, wherein:

Figure 1 shows a side elevation of a derrick with the elevator equipmentinstalled.

35 Figure 2 shows a fragmentary, side view of the cable sheaves at thetop of the derrick.

Figure 3 shows a horizontal, cross-sectional view of the elevator car.

Figured shows a side elevation of the elevator 40 car framework andillustrating the brake mechanism.

Referring now more particularly to the drawing wherein like numerals ofreference designate the same parts in each of the figures, the nu- 45meral l designates a conventional type of derrick as a who-1e having thecorner legs 2, 2 connected by the horizontal cross-bars 3 which aresuitably anchored tothe corresponding corner legs.

50 At one side of the derrick there is a vertical track formed of spacedchannel irons, 4, 4, the flanges of said channel irons being turnedoutwardly.

As clearly illustrated in Figures 1 and 4 these II channel irons areformed in sections for convenience in erection and dismantling. Asclearly illustrated in Figure 3 the channels of each section may 'beconnected in assembled relation by means of the inner and outercross-straps as '5, 6 which may be welded or otherwise secured to thechannels. The inner cross-straps extend each way beyond the channels 4and said extended ends form means whereby the inner cross-straps may besecured to the corresponding cross-bar 3 in any suitable manner as 19 bymeans of U-bolts "l as shown in Figure 3. It is obvious that the trackmay be thus erected a section at a time and may be dismantled byreleasing the U-bolts 1.

At the upper end of the track andfixed on the transverse shaft 8 thereis a sheave 9. The

shaft '8 is mounted to rotate in suitable bearings l0 which are carriedby the-side members of the track.

Fixedon the shaft 8 there is agear ll which 20 is in mesh with the worml2 on the outer end of which is fixed a sheave I3.

The numeral l4 designates the skeleton framework of the elevator car.The walls of said car are preferably formed of heavy wire mesh and linedwith asbestos. It is provided with a door It for the ingress and exit ofthe passengers. The car is suspended by means of a wire line l1 one endof which is attached to the top of the car. Said wire line works overthe sheave 9 and its other end carries a counterweight l8 which moves inthe well l9 between the channels 4.

Secured to the inner side of the car are the upper and lower sidebrackets 20, 2| and rotatably mounted on these brackets are the upperand lower wheels 22, 23 which run in the channels 4.

There is the endless cable 24 which works over the sheave I3 at the topof the track and over a corresponding sheave 25 at the lower end of thetrack, said cable working through suitable guideways, 26, 21 provided inthe elevator car.

The occupant of the car may manipulate the cable 24 in one direction soas to drive the sheave l3 in the same direction to rotate the sheave 9 4correspondingly so as to elevate the car. The car will be held againstdownward movement by gravity by the gearing ll, I2, the pitch of saidgearing being such as to support the normal weight of the car with theoccupant therein. So when it is desired to descend the operator willmanipulate said cable 24 in the other direction so as to move the cardownwardly. There will, accordingly, be no danger of the sudden descentof the car except in case of breakage of the line H.

To guard against the sudden descent of the elevator car, in the event ofbreakage of the wire line H, an automatic brake mechanism has beenprovided. It comprises a hanger 28 which is pivoted, at its upper end,on the skeleton framework of the car. Pivotally connected to the lowerend of the hanger 28 there is a brake bar 29. One end of this brake barcarries an arcuate brake shoe 30 which is pivoted thereto and the upperend of the link 3| is pivotally connected. to the other end of saidbrake bar. The lower end of the link is pivotally connected to a brakepedal pivoted to the skeleton framework of the car. It'will be seen,therefore, that the brake bar 29 and the hanger 28 may swingtransversely about the pivoted end of the latter. Fixed to the brake bar29 and extending upwardly therefrom there is an arm 33 whose upper endis overturned and has a sheave 34 mounted to rotate thereon and tonormally run on the wire line H. The arm 33 is of such length that whenthe sheave 34 is bearing against the Wire line H the brake shoe 30 willbe held centered between the flanges of the corresponding channel 4. Theshoe, however, will be held out of contact with the wheel 22 by the pullspring which is attached at one end to the brake bar opposite the shoe3!) and at its other end to the top of the skeleton framework of thecar, Should the wire line I! break the weight of the upper end of thearm 33 will overbalance the brake bar and brake shoe and will cause saidshoe 3!] to move into braking contact with the wheel 22 and the lateralswinging movement of the bar 29 will permit said shoe to move laterallyinto contact with the opposing flange of the channel iron 4 and wedgebetween said flange and the wheel 22 thus increasing the braking effect.This action will be automatic. The braking effect, however, may beaccentuated by the occupant of the car by pressing on the foot pedal 32.

When the car has been elevated to a point adjacent the derrickmansplatform in the derrick it will remain in that position due to thebalancing influence of the counterweight I8 but it should be latched inthat position to prevent its being moved by manipulation of the cable 24by someone at the ground surface so that it will always be in readinessfor the derrick man to descend. Any suitable type of latch mechanismsuch as 36 may be mounted on the car to be engaged with, or disengagedfrom, a cross-strap 1' 6 at the will of the operator of the elevatorcar.

Thecdrawing and description are illustrative merely, while the broadprinciple of the invention will be defined by the appended claims.

What ,I claim is:

1. Elevator equipment for a derrick, comprising a' track formed ofsections, attaching means for attaching the sections, in end to endrelation, to the derrick to form an approximately vertical track, anelevator car having wheels movable along the track, means for elevatingand lowering the car and brake means arranged to co-actwith a wheel andthe track to control the descent of the car.

2. Elevator equipment for a derrick, comprising a track mountedvertically on the derrick, an elevator car having wheels movable alongthe track, means for elevating and lowering the car, brake mechanism,mounted to swing transversely of the car and including a brake shoepositioned to wedge between a car wheel and the track when the brakemechanism is in active position and means normally holding said brakemechanism inactive.

CRAWFORD K. STILLWAGON.

